Articles techniques et présentations

Many liquid food processes involve coupled phenomena of fluid flow, heat transfer and product transformation. A typical example is the heat treatment of a starch suspension inside a tubular heat exchanger. Fluid flow influences heat transfer which determines temperature evolution along ... En savoir plus

A novel numerical method characterizing groundwater flow in unconfined aquifer is demonstrated. In contrast to the conventional method (Dupuit approach considering horizontal flow only), hydraulic head is simulated in horizontal and vertical directions. The new approach is introduced via ... En savoir plus

The present study relates to the reduction of the amount of air to gas leakage in a typical rotary regenerative air preheater of coal-fired steam generators, by means of computational thermo-fluid-dynamics. Due to the gaps, or clearances, required for rotation, there is a significant ... En savoir plus

In a hydronic space heating system the heat output arises from natural convection and radiation from the radiators. In order to increase the heat output, without replacing the radiators with larger ones, or increasing the temperature level, the radiator can be equipped with add-onfan ... En savoir plus

During the last decades, mid-IR (3-12µm) laser sources have attracted attention due to their potential applications in different fields like infrared counter-measures (e.g: missile jamming) and remote chemical sensing. In this context, Onera has been working on the development of non ... En savoir plus

Ectopeptidases are commonly accepted to be a means of clearing active peptides. However, studies have shown that they can also regulate peptide activity. We have developed a technique of electrokinetic push-pull perfusion (Ek-PPP, Figure 1) to examine this largely unexplored mechanism of ... En savoir plus

Although there are porous media and subsurface flow modes available in a toolbox of COMSOL Multiphysics®, some common requirements in hydrogeological models can not be easily accessed in the graphical user interface. Most crucially, there is no distinction between confined and unconfined ... En savoir plus

This paper presents preliminary estimations of CO2 overpressure into the reservoir and CO2 leakage through the caprock and the overburden. A simple, two-phase flow model in porous media based on Darcy’s law was used, in order to explore easily long time periods. The models produced by ... En savoir plus

Knowledge of the effect of fractures on fluid flow and transport is of great interest in many fields. In radioactive waste disposal the interest in fractures within concrete structure is because they are mostly more permeable than the matrix, there is less or no sorption and because long ... En savoir plus

Transformers, as any other industrial products, have to comply with various requirements on noise levels. Three main sources of noise can be identified in transformers: no-load noise or core noise generated by magnetostriction in the core steel laminations, load noise produced by ... En savoir plus